CLOSE
Christof Stache/AFP/Getty Images
Christof Stache/AFP/Getty Images

8 Climatic Facts About Our Abnormally Warm Winter

Christof Stache/AFP/Getty Images
Christof Stache/AFP/Getty Images

It was warm this winter. Freakishly warm, in fact. It was warm enough that we probably should have felt guilty for enjoying it so much. After all, any time you can open your windows when you’re supposed to be shivering and watching travel shows for warmth is a strange situation. Most of the United States just lived through one of the warmest Februarys on record to close out one of the warmest winters on record. Here are some statistics that will show you just how unusually balmy it’s been for the past three months.

1. THIS FEBRUARY WAS WARMER THAN NORMAL.

A map of how warm this February was compared to previous years. Stations showing a ‘1’ experienced the warmest February ever recorded at that location. Image Credit: SERCC

 
It shouldn’t come as any shock that February’s temperatures were above-average when you crunch the numbers. Out of 888 weather observing stations across the lower 48, a solid 60 percent of those stations (or 534 locations) saw their top-10 warmest February on record this year. Even worse is that 186 of those locations—scattered from the depths of Texas to the Canadian border—recorded their all-time warmest February, with some records stretching back more than 100 years.

2. THE WHOLE WINTER WAS WARMER THAN NORMAL.

Not only was this past February a record-breaker, but the whole winter was warm on average. Data from the Southeast Regional Climate Center shows that over half of those 888 weather observing stations in the contiguous United States saw this winter place among the top ten warmest winters ever recorded, with almost all of the toasty stations residing east of the Rocky Mountains. Most of the all-time warmest winter records were set in the southern part of the country, including cities like Houston, Texas, and Raleigh, North Carolina.

3. THE WARMTH KEPT MOST OF THE SNOW AT BAY.

Taken just one day apart in early February, two views of the downtown Manhattan skyline—one warm and sunny, the other obscured by snow—as seen from the Brooklyn Heights Promenade. Image Credit: Spencer Platt/Getty Images

 
As you can imagine, you’re not going to find very much snow when it’s relatively toasty out there. There have been other winters with less snow than most places saw this year, but the differences are negligible. Take Washington D.C., for example. Washington National Airport, which sits just across the Potomac River from the capital city itself, typically sees about 15 inches of snow every year. They’ve recorded just over an inch of snow this year. On the list of least-snowy winters in the nation’s capital, this winter ranks fourth since records began in 1940.

4. CHICAGO SAW NO SNOW IN JANUARY OR FEBRUARY.

Even more unusual is the fact that Chicago went through the entire months of January and February without seeing one lick of snow cover the ground. According to the city’s National Weather Service office, this was the first time in the city’s 146 years of recording weather observations that they didn’t see any snow on the ground during the dead of winter. The city saw a foot-and-a-half of snow spread out over several storms during the month of December, but all of that snow melted by Christmas. The most they’ve seen since then is a “trace” of snow, which is snow that falls but instantly melts when it hits the ground.

5. THE GREAT LAKES WERE RELATIVELY ICE-FREE.

While we’re looking toward the Midwest, it’s worth noting that the Great Lakes were surprisingly ice-free this season. The five lakes only saw about 15 percent of their surface covered by ice during the season’s maximum extent on February 8, and what little ice did form this year is rapidly melting as warm air continues to bathe the enormous bodies of water. Since NOAA began keeping records back in 1973, a typical winter sees a little more than half of the Great Lakes covered with ice during the peak of winter, but the coverage has been as low as 11 percent, a record achieved in 2002.

6. THE LEAVES LOVED IT, THOUGH.

A map showing how unusually early (or late) leaves first showed up on trees in 2017 compared to normal. Image Credit: USANPN

Humans aren’t the only organisms enjoying the reprieve from winter’s grip. The USA National Phenology Network tracks the extent of trees budding and growing leaves as spring begins to set in. According to their observations, almost every part of the United States that has leaves on its trees right now saw those leaves appear a full three weeks ahead of schedule—what it calls "very large anomalies." This is welcome news for the birds and the bees, but if there’s a sudden cold snap in March—which isn’t unheard of—it could do some serious damage to any plants that are suddenly more vulnerable than normal.

7. THE WARMTH LED TO SOME SEVERE THUNDERSTORMS.

When you put an active weather pattern together with warm and unstable air, it’s almost inevitable that you’ll wind up with strong thunderstorms at some point. We saw several rounds of severe weather this spring, resulting in at least three fatalities on the last day of February. Severe weather is fairly common in the southeast due to its proximity to muggy air over the Gulf of Mexico, but severe weather stretched unusually far north this year. A tornado that touched down in western Massachusetts on February 25 was the only tornado ever recorded in the state during the month of February, and quite possibly the farthest north we’ve ever seen a tornado since reliable records began in 1950.

8. SO WHY HAS IT BEEN SO WARM?

Why has it been so warm in the east and so cool and active out west? It has to do with the jet stream. For the past couple of years, there’s been a huge ridge in the jet stream over the West Coast that kept them warm and dangerously dry, while the jet stream dipped south and brought cooler, more active weather to the rest of the United States. That pattern broke this year, essentially reversing itself and keeping the warmth-inducing ridge out east while the jet stream in the west keeps dipping south and bringing them a steady stream of rough weather. One theory as to why the pattern flipped is the disappearance of the infamous “Blob,” a nickname given to an unusually warm area of water in the northeastern Pacific Ocean. That water cooled off, which may have allowed the jet stream to readjust itself into the pattern we’ve seen this winter.

nextArticle.image_alt|e
iStock
arrow
Weather Watch
Thanks to Desert Dust, Eastern Europe Is Covered in Orange Snow
iStock
iStock

Certain areas of Eastern Europe are starting to look a bit like Mars. Over the last few days, snowy places like Sochi, Russia have experienced an unusual snowfall that coated mountains in orange powder, according to the BBC.

The orange snow was the result of winds blowing sand from the Sahara east to places like Moldova, Romania, Bulgaria, Ukraine, and Russia. The sand mixes with precipitation to form orange-tinted snow. According to the BBC, the phenomenon occurs semi-regularly, turning snow orange about once every five years, but this year is especially sandy. As a result, skiers are navigating slopes that look like they're from a different world, as you can see in the video below from The Guardian.

The Sahara rarely gets snow, but when it does, the landscape can look somewhat similar, as you can see in this image of the Atlas mountains in Morocco.

Instagram is currently filled with photos and videos from Eastern Europe featuring the odd-looking snow. Check out a few samples below.

[h/t BBC]

nextArticle.image_alt|e
Jessica Kourkounis, Getty Images
arrow
Weather Watch
What Is Thundersnow?
Jessica Kourkounis, Getty Images
Jessica Kourkounis, Getty Images

The northeastern United States is dealing with its second major nor'easter in a week, with rain and heavy snow—and the associated power outages—cutting a path across the Mid-Atlantic and New England. But news of the adverse impacts of the snowstorm is being accompanied by an unusual buzzword: thundersnow. Thundersnow occurs during a thunderstorm that produces snow instead of rain. The mechanisms that produce rainy thunderstorms and snowy thunderstorms are largely the same, even if the air temperature is below freezing.

A band of snow can become strong enough to produce lightning through two processes known as convection and forcing. Convection occurs when an area of warm air quickly rises through cooler air above it. Convective snow is most common during lake effect snow events like those you’d find on Lake Ontario or Lake Erie, since the process requires extreme vertical temperature gradients that can result from bitterly cold air flowing over a warm body of water.

Forcing is slightly different. A strengthening low-pressure system involves fast, dynamic changes in the atmosphere, especially when one of these storm systems quickly gains strength. Such a fast-developing storm can cause large amounts of lift in the atmosphere, a process that forces air to swiftly rise like you’d see during convection. This creates intense bands of snow that can grow so strong that they produce thunder and lightning. This process is responsible for the thundersnow that occurs during blizzards and nor’easters, those powerful storms that regularly hit the eastern coast of the U.S. during the winter. Thundersnow can be pretty exciting—just ask The Weather Channel's Jim Cantore:

The name “thundersnow” can be a bit misleading. One of the most enjoyable things about a snowfall is how silent it is outside when there’s a thick blanket of snow on the ground. Snow absorbs sound waves so efficiently that you can usually only hear ambient noises immediately around where you’re standing. Snow muffles the sound of thunder for the same reason. Thunder that might be audible for many miles during a rainy thunderstorm might only be audible for a few thousand feet away from where the lightning struck. Unless the lightning strikes very close to where you are, you might only see a bright flash during thundersnow without ever hearing the thunder.

While thundersnow is a fascinating phenomenon to encounter, it does involve lightning, after all, and it’s just as dangerous as any other lightning bolt you’d see in a rainy thunderstorm. If you’re ever lucky enough to experience thundersnow, the event is best enjoyed indoors and out of harm’s way.

This piece originally ran in 2017.

SECTIONS

arrow
LIVE SMARTER
More from mental floss studios